Witnesses told police that Ramos allegedly came in through the side door of the Little Doggie around 5 p.m., immediately walked up to Cantu, who was sitting in the bar, and shot him in the head, Goetschius said.

Cantu, who is Ramos' father-in-law, died instantly.

"In my career, this is truly what appears to be an execution-style murder with no warning or provocation," Goetschius said. While the motive is still under investigation, police said it appears Ramos shot his father-in-law to get back at his wife whom he was having problems with.

Fighting outside bar

Commotion then erupted in the bar. As Ramos attempted to leave, Robinson tried to tackle him, Goetschius said.

The two men ended up outside the bar, where Ramos allegedly shot Robinson at least one time before another bar patron rushed over to help, Goetschius said.

That man took the gun from Ramos and struck him repeatedly, Goetschius said.

Robinson was taken to the University of Texas Medical Branch, where he later died. A woman at the jukebox in the bar was struck in the shoulder by a bullet. She was also taken to UTMB and is expected to survive.

A Texas City police officer on routine patrol heard the shots coming from the bar and spotted the commotion. He saw Ramos being held on the ground and the bar patron with the gun in his hand, Goetschius said.

The officer ordered the man to drop the weapon and was informed by the patron that the gun belonged to Ramos.

Ramos was taken into custody and is currently being held at Texas City Jail. His bail is set at $750,000.